KareenaBaby

hello guys. im thinking about doing an oil change for my version3 sti. i have a 5litre bottle of GTX castrol 15 40w oil. is this oil ok to use? what is the difference between 10 & 15?

what is the best 1 to use.

thank uuu x

SunnySideUp

I would strongly advise you NOT to use that.

You need a 10W 40 Semi Synthetic, COMMA do a fantastic Oil for £13 - that's 5 Litres too

http://www.commaoil.com/Product%20%2...cants/lite.gif

Some will come on here saying you must buy some expensive oil as it's better - truth is the COMMA Oil meets all of the specifications that Subaru specify as being required. Just because it's not called something like "RallyX SuperDuper XXXtra protection Racing Fast Oil" means nothing ... don't get blinded by marketing techniques

Just my opinion .... and what I do, and have done for many years and miles without issue.

bighead

iTrader: (1)

well its like saying FERRARI is the same as FORD , you always pay for what you get (they are expensive for a reason )

Peanuts

iTrader: (15)

Kareena, please consider putting your posts in the correct section.
It makes for more pleasant reading thanks

ALi-B

iTrader: (1)

Quick Answer: No!

Long Answer (below):

Viscosity wise that oil is ok. 15w-40 is acceptable (15w means it thicker when cold, but when hot its the same as a 0w-40, 5w-40, 10w-40 etc). Although not not ideal in the UK climate, it uses a thicker base stock which should help it stay in grade at high temps.

BUT: GTX is just basic mineral oil.

I don't think it complies with the relevant ACEA / APi standards needed for old shape Imprezas. It should only be used in basic old fashioned engines. (no doubt it says for "basic/high mileage engines" on the bottle -marketing BS )

Unless you plan on changing the oil every 3months/3K and don't drive very hard. I wouldn't touch it, as the temperature and loads of the engine will make the oil break down sooner, and thus require changing more regularly.

Better to a spend a bit more money and at the very least use a semi synthetic of which should stay within specifications for the standard 6months/6K oil change interval.

What grade and spec is down to how you drive the car: lots of cold starts would point to a oil with a lower number before the "w" hard driving and heavily modified engine would need a high number after the "w". An engine thats used for lots of short journeys (less than 30mins) or driven hard will need the oil changing more regularly unless a better quality oil is used (i.e a synthetic over a semi-synthetic).

Don't be hoodwinked too much by "synthetic" branded oils; most use mineral basestocks so really are just premium semi-synthetics, "true" synthetics (usually ester based) are much more expensive.

The choice is yours; 10w40 semi for normal use. 10w-50 or 15w-50 synthetic for harder use, 5w-40 synthetic for tottering round town with the rare blast inbetween.

However; GTX 15w-40 is perfect for the lawn mower


<now moving thread to general tech >

SunnySideUp

You are absolutely correct ....... just make sure it's not expensive because numpties are will to pay big bucks!!

KareenaBaby

ok thanks im not guna touch it now, it was actually suppose to be for my dads laguna.

please could sum1 recommend a good oil brand that i can buy from halfords?

thanks

rezaP1

KareenaBaby i think halfrauds only do Mobil, Castrol and Halfords (Own Brand). Personally i wouldn't use neither of them incase the . I'd visit or email the lads at opie oils. There are great bunch of lads and will help and advise as best they can.

I ordered Silkolene Pro S ester synthetic 10w-50 the other week which is about the best you can get and the choice of many subaru specialists ( some others are Motul M300V 15-50 or Millers 10-40 ) and it was here the next day Click here for opie oils website

Its got to be worth the money putting in the best stuff in. You wouldnt spend loads on handling to use cheapo tyres or buy big AP brakes with cheapo pads. Same should apply to engine ...

( if you cant be a*sed with all that and want just want to buy immediately i'd head to a shell petrol station and buy some shell helix plus 10w-40 )

stigaz

opie oils recommend mobil and castrol among others for the impreza

joz8968

iTrader: (13)

Everything you wanted to know, but were too afraid to ask ...

https://www.scoobynet.com/technical-...-answered.html

Peanuts

iTrader: (15)

Do Opie oils recommend brands that they don't stock in any of their "papers"?

stigaz

dont stock??not sure what you meen about papers , but look hereCar Engine Oils

i'm not saying that mobil or castrol are better or as good as but opie oils sell them for the subaru impreza, if you want to pay the extra then silkolene and motul are the two to choose from.

i will be paying the extra btw